Medical diagnostic test strips are used in a variety of applications. Such strips are exposed to samples of blood, feces, or urine, for example, where specific reagents on the test strip are designed to detect various components in the sample. Medical diagnostic test strips are specifically used to detect the level of glucose in a patient's blood. Such test strips must be exposed to an atmosphere that is substantially moisture-free until moments before use in testing a sample. The strips are often highly water absorbent, and absorption of moisture may alter test results.
Accordingly, the known industry practice for keeping the test strips dry is to contain a plurality of such test strips in a container or vial. The cap for the container has a desiccant contained in it to absorb water from the air inside the container. In this manner, the strips within the container are kept dry. When ultimately used, a doctor or other testing personnel, including a patient himself, removes the cap from the container, extracts one of the test strips, and immediately places it in the sample to be tested (or places a small quantity of the sample to be tested on the test strip) Exposure of the strips to the ambient atmosphere before use is thus minimized to reduce water vapor absorption by the test strip.
A disadvantage of this technique is that all of the strips within the vial must be used within a relatively short time after the vial is first opened or they cannot be reliably used. The time period is usually on the order of a few months. Because of the exposure to the ambient atmosphere upon opening, there is a risk that the test strips will absorb enough moisture to render them ineffective in this amount of time despite the presence of the desiccant in the cap. In addition, there are manufacturing, packaging, and use complications resulting from the inclusion of multiple test strips in a single vial according to prior practice. It is therefore desirable to provide individual test strips with the ability to resist water absorption. This would provide efficiencies in manufacturing, packaging, and using the strips.